丹皮酚对脂多糖诱导的星形胶质细胞炎性因子分泌的影响

Effects of paeonol on release of inflammatory cytokines induced by lipopolysaccharide in cultured astrocytes

目的观察丹皮酚对体外培养的星形胶质细胞炎性因子分泌的影响,并探讨其作用机制。方法采用神经胶质原纤维酸性蛋白(GFAP)免疫荧光染色法鉴定星形胶质细胞;实验分为对照组,模型组和2.5、5、10μmol·L-1丹皮酚组,0.5 mg·L-1脂多糖(LPS)诱导炎症反应。采用ELISA法测定培养液中白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)水平;采用Western blot检测细胞IκBα蛋白表达和磷酸化水平及胞核NF-κB(p65)蛋白表达水平。结果与对照组相比,模型组星形胶质细胞上清液中IL-1β、IL-6和TNF-α水平显著增加(P<0.01),胞浆IκBα蛋白表达受抑(P<0.01),IκBα蛋白磷酸化和胞核NF-κB(p65)蛋白表达水平上调(P<0.01);5、10μmol·L-1丹皮酚能减少LPS活化的星形胶质细胞上清液中IL-1β、IL-6和TNF-α水平(P<0.05或P<0.01),增加胞浆IκBα蛋白表达(P<0.05或P<0.01),抑制LPS上调的IκBα蛋白磷酸化和胞核NF-κB(p65)蛋白表达水平(P<0.05或P<0.01)。结论丹皮酚能抑制LPS诱导的星形胶质细胞炎性因子IL-1β、IL-6和TNF-α的分泌,IκBα/NF-κB信号通路可能参与了丹皮酚对星形胶质细胞炎症反应的抑制作用。

METHODS Cultured astrocytes identification was evaluated by immunocytochemically stained with glial fibrillary acidic protein （GFAP）. The cells were divided into control group, model group, and the 2.5, 5 and 10 μmol·L^-1 paeonol groups. LPS （0.5 mg·L^-1） was used to induce the inflammation. Proinflammatory cytokines IL-1β, IL-6 and TNF- α were determined by ELISA. Western blot was performed to observe the protein expression and phosphorylation levels of IκBα, and the protein expression of nuclear NF-κB （p65） in cultured astrocytes. RESULTS The levels of IL-1β, IL-6 and TNF- α in cell culture supernatant were significantly increased in the model group （P 〈 0.01 ）, and the phosphorylation levels of IκBα and the protein expression of NF- κB （p65） were up regulated （P 〈 0.01 ）, and the protein expression of IκBα in cultured astrocytes was down regulated （P 〈 0.01）. The levels of IL-1/3, IL-6 and TNF-α in cell culture supernatant were significantly decreased （ P 〈 0.05 or P 〈 0.01） , LPS induced overexpression of NF - κB （p65） and phosphorylation levels of IκBα were inhibited （P 〈 0.05 or P 〈 0.01 ）, and the protein expression of IκBα was increased in the 5, 10 μmol·L^-1 paeonol groups （P 〈 0.05 or P 〈 0.01）. CONCLUSION Paeonol can inhibit the release of inflammatory cytokines induced by LPS in cultured astrocytes through the suppression of IκBα/NF- κB signal transduction pathway activity.